Isolation and characterization of two genes encoding polygalacturonase-inhibiting protein from Populus deltoides.
Polygalacturonase-inhibiting proteins (PGIPs) are extracellular proteins that belong to the leucine-rich repeat (LRR) protein superfamily. PGIPs inhibit fungal polygalacturonases (PGs) and promote accumulation of oligogalacturonides, which activate plant defense responses. PGIPs play important roles in resistance to infection of pathogens. In this study, reverse transcriptase-polymerase chain reaction (RT-PCR) and RNA ligase-mediated rapid amplification of cDNA ends (RLM-RACE) were used to isolate the full-length PGIP cDNA from Populus deltoides (GenBank accession no. of PdPGIP2 and PdPGIP4: EF684913 and EF684912). Domain analysis revealed that the deduced amino acid sequences of PdPGIP2 and PdPGIP4 had a typical PGIP topology. Phylogenetic analysis of known PGIPs indicated that the two PdPGIPs were clustered to the defense-related PGIP clade. Using real-time RT-PCR, the expression patterns of the two PdPGIPs following treatment with a fungal pathogen and defense-related signaling molecules were studied. The expression levels of PdPGIP2 and PdPGIP4 were both up-regulated when inoculated with the phytopathogenic fungus Marssonina brunnea. Therefore, it was proposed that the two PGIPs might be involved in the resistance to Marssonina brunnea in P. deltoides.
Cheng
Qiang
Q
Key Laboratory of Genetics & Biotechnology, Ministry of Education, Nanjing Forestry University, Nanjing 210037, China.
Cao
Youzhi
Y
Pan
Huixin
H
Wang
Mingxiu
M
Huang
Minren
M
D000595:Amino Acid Sequence; D003001:Cloning, Molecular; D017124:Conserved Sequence; D018076:DNA, Complementary / Q000235:genetics; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D017343:Genes, Plant; D008969:Molecular Sequence Data; D010802:Phylogeny; D010937:Plant Growth Regulators / Q000494:pharmacology; D010940:Plant Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D032107:Populus / Q000187:drug effects / Q000235:genetics* / Q000502:physiology; D015398:Signal Transduction / Q000235:genetics; D013312:Stress, Physiological / Q000235:genetics
D018076:DNA, Complementary; C081479:PGIP protein, plant; D010937:Plant Growth Regulators; D010940:Plant Proteins